Added message for unsupported browsers

src/_includes/layouts/base.njk

@@ -26,5 +26,15 @@
       });
     }
   </script>
+  <script> 
+    var $buoop = {required:{e:-4,f:-3,o:-3,s:-1,c:-3},insecure:true,api:2021.04 }; 
+    function $buo_f(){ 
+    var e = document.createElement("script"); 
+    e.src = "//browser-update.org/update.min.js"; 
+    document.body.appendChild(e);
+    };
+    try {document.addEventListener("DOMContentLoaded", $buo_f,false)}
+    catch(e){window.attachEvent("onload", $buo_f)}
+  </script>
 </body>
 </html>